"""Add audited compute-node decommission tombstones and operation records.

Revision ID: 20260828_0022
Revises: 20260827_0021
"""

from collections.abc import Sequence

import sqlalchemy as sa

from alembic import op

revision: str = "20260828_0022"
down_revision: str | None = "20260827_0021"
branch_labels: str | Sequence[str] | None = None
depends_on: str | Sequence[str] | None = None


def upgrade() -> None:
    op.add_column(
        "compute_nodes",
        sa.Column("generation", sa.BigInteger(), nullable=False, server_default="1"),
    )
    op.add_column("compute_nodes", sa.Column("decommissioned_at", sa.DateTime(timezone=True)))
    op.add_column("compute_nodes", sa.Column("decommission_reason", sa.Text()))
    op.add_column("compute_nodes", sa.Column("decommissioned_by", sa.String(255)))
    op.create_index("ix_compute_nodes_decommissioned_at", "compute_nodes", ["decommissioned_at"])
    op.create_table(
        "node_decommission_operations",
        sa.Column("id", sa.Uuid(), primary_key=True, nullable=False),
        sa.Column(
            "compute_node_id",
            sa.Uuid(),
            sa.ForeignKey("compute_nodes.id", ondelete="RESTRICT"),
            nullable=False,
        ),
        sa.Column("persisted_identity", sa.String(128), nullable=False),
        sa.Column("idempotency_key", sa.String(128), nullable=False),
        sa.Column("expected_generation", sa.BigInteger(), nullable=False),
        sa.Column("preview_digest", sa.String(64), nullable=False),
        sa.Column("reason", sa.Text(), nullable=False),
        sa.Column("operator", sa.String(255), nullable=False),
        sa.Column("previous_state", sa.JSON(), nullable=False),
        sa.Column("cleanup_summary", sa.JSON(), nullable=False),
        sa.Column("status", sa.String(32), nullable=False, server_default="completed"),
        sa.Column(
            "created_at",
            sa.DateTime(timezone=True),
            nullable=False,
            server_default=sa.func.now(),
        ),
        sa.Column("decommissioned_at", sa.DateTime(timezone=True), nullable=False),
        sa.UniqueConstraint("compute_node_id", name="uq_node_decommission_node"),
        sa.UniqueConstraint("idempotency_key", name="uq_node_decommission_idempotency"),
        sa.CheckConstraint("expected_generation >= 1", name="ck_node_decommission_generation"),
    )
    for column in ("compute_node_id", "persisted_identity", "status", "decommissioned_at"):
        op.create_index(
            f"ix_node_decommission_operations_{column}",
            "node_decommission_operations",
            [column],
        )


def downgrade() -> None:
    op.drop_table("node_decommission_operations")
    op.drop_index("ix_compute_nodes_decommissioned_at", table_name="compute_nodes")
    op.drop_column("compute_nodes", "decommissioned_by")
    op.drop_column("compute_nodes", "decommission_reason")
    op.drop_column("compute_nodes", "decommissioned_at")
    op.drop_column("compute_nodes", "generation")